mallory



3 Sheets-Sheet l.

(No Model.)`

W. H. MALLORY.

STEERING PROPBLLER.

No. 249,191.V

Patented Nov. 8,1881.

IJ4 PETERS. Phulo-Lihagnwber, Wnthmgkm. D. C.

' (No Model.)

3 Sheets-Sheet 2.

W.V H. MALLORY. STEERING PROPELLBB..

Patented Nov. 8, 1881.

No. 249,191". l

UNITED STATES PATENT OFFICE.

WILLIAM H. MALLORY, OF BRIDGEPORT, OONNEGTICUT, ASSIGNOR TO THE AMERICAN PROPELLER COMPANY, OF SAME PLAGE.

STEERING-PROPELLER.

SPECIFICATION forming part of Letters Patent No. 249,191, dated November 8, 1881.

Application filed April 14, 1881. (No model.)

Togall whom it may concern:

Be it known thatI, WILLIAM H. MALLORY, of BridgeporaConnecticut, have invented a new and useful Improvement in Propellers for Vessels, of which the following is a full, true, and exact description, reference being had to the accompanying drawings.

It has been long known as avery desirable end to be accomplished to construct a vessel which might be capable of being controlled both as to movement and direction by its propeller wheel or wheels. The idea of using the propeller1 as a rudder to steer the vessel by changing its relation to the vessel is old in the art. In a previous patent (granted to me on the 23d day of June, 1874) I have shown a method of steering, stopping, and backing a vessel by varying the plane of rotation of the propeller-wheel with relation to the line ofthe vessel. Owing, however, to the lateral thrust of the engine, a propeller-wheel is constantly tending to move laterally or around its vertical` support in the direction in which the vertical driving-shaft revolves, when arranged in such a form as I have described.

It has been found necessary to apply a very great force in order to control the position of the propeller-wheel around its vertical axis 5 and my present invention is designed especially to overcome this difficulty by combining a double propeller to form an apparatus which can be readily moved about its center support in` both directions without the'application of any considerable force, and this is done primarily by lmeans ofthe peculiar mechanism` shown the double wheel can be revolved freely completely around its central support.

My invention will be readily understood from the accompanying drawings, in which-4 Figure 1 represents aver-tical section througli my propeller-driving mechanism, taken longitudinally of the vessel; Fig. 2, a view, partly in section and partlyin perspective,`ot` portions of myappara'tus; and Fig. 3, a detailed view of 5 5 the method of connecting my propeller-wheels to the central support, being a section through Fig. 1 on the line a; a'.

My apparatus consists, primaril y,` of two propeller-wheels, A and B, mounted opposite to each other on the same center of support or casing F. This casing rests in a socket, K, and may be revolved around its vertical axis. y The method of supportingthepropeller-hubs and ot' attaching them to the centercasing, F, is clea-rlyshown in Fig.3; but any other practicable method may be used. The construction shown in Fig. 3 is as follows: The thrust of the propeller is received upon the thrustrings (l upon the center shafts, (1 which are permanently connected to the casingF. Parted or double sleeves b b are -constructed to exactly tit, when united, the shafts a., provided `with thrust-rings d. The miter-gears L and M screw over and inclose the innerends of these parted sleeves, and the propeller hubs pass over and inclose their outer portions. When the propellers areplaced in position and `keyed upon the sleeve in the usual Way the whole forms a complete and solid mechanism, not liable to become loose, and at the same time affording sutlicient bearing-surface to receive the thrust of the propellers. These propellerhubs are provided on their inner extremities with miter-gears L and M, by means of which they are rotated. The power to operate these propellers is derived from the engine-shaft E, provided with miter-gear G. This miter-gear G gears into two other miter-gears, H and J, wlIiclImiter-gears are thereby revolved in opposite directions. Connected with the mitergear J is the hollowr shaft C, provided at its lower extremity with miter-gear `P.. This mi* ter-gear yI? gears with the miter-gear Ii, attached to propeller A. The miter-gear ,EI is 95 attached to a center shaft, D, which stands in the axis of the revolving mechanism supporting the propellers. Attached to the center shaft, D, is the miter-gear R, which gearsA with the ruiter-gear M, which drives the propeller"roo e Maier B. The position ofthe casing F is determined by the worm-screw S gearing in the wormwheel V. The worm-screw S is rotated by a shaft, T. o

The operation of my apparatus will now be readily understood. The engine being put in operation, the shaft E operates the miter-gears H and J. The mitergear H operates the shalt D, which rotates the propeller B by intermediate imiter-gears, It and M. The miter-gearJ operates the hollow shaft C aud the propeller A'by means of the miler-gears Pand L.

It will be observed that the two propellers A and B are not set upon the same horizontal axis, in order that the miter-gears connected ith them may gear with the miter-gears of t e shaft and sleeve` respectively. lf the gears were properly made, itis plain that this division of the engine-thrust might be accomplished having all four of the miter-gears M, P, L, and It gear together, when the same result might be accomplished; but, owing to the difficulties of this construction, l prefer the construction shown in the drawings, which absolutely divides the thrust of the engine.

One of the difficulties interfering uith the easy manipulation of this class ot' self-steering propellers has been that the thrust or force of the engine necessarily tended to twist the propeller-case around its verticaLaxis, the en-v gine-force being necessarily applied at a point laterally more or lessdistant from the central vertical axis of the propeller-supporting mechanism.

The principal object of this improvement is to produce an apparatus'in which the lateral v thrust of the engine or the tendency to twist is necessarily thrown upon what we may call the steering mechanism 7 ofkthe propeller. By the arrangement shown this strain is entirely removed fromv the steering mechanism, and this is accomplished by dividing the thrust of the engine, as communicated through the gears,into two equal and opposite forces, which counteract each other in their resultant effect upon the propeller and upon the steering mechanism of the propeller. Snpposing the apparatus to beoperatediu the direction shown by the arrow in Fig. 2, the tendency of the engine will be to throw the forward end of the miter-gear H to the right and the'forward end of the-miter-gear J to the left. Through the shaft E and hollow shaft C this force will be communicated to the mitcr-gears R and P. In the position shown in Fig. 3 the tendency of the miter-gear P will be to throw the mitergearL to theleft, and thereby to twist the front of the casing in the direction shown by the arrow y, while the tendency of the ruiter-geary R, operating upon the miter-gear M, will be to twist themiter-gear M to the right, and therefore to twist the casing in the direction shown by the arrow y. lonsequently the casing, being acted upon by two equal and opposite forces tending to twist it around its center in opposite directions, can be, so far as these forces are concerned, freely moved into any position.

It will also be seen that bythe construction of my apparatus the double screws can be rotated completely around their axis of support.

The position of the casing is readily determined by means of the worm-wheel and gear S V, as before described. By this arrangement the double propellercan be readily swung completely around its axis in either direction, and thevessel can beinstantly steered, stopped or reversed.

This` invention is particularly applicable to torpedo -boats, launches, and other war vessels, but may be used in combination with any steam-propelled vessel.

What I claim as myinvention, and desire to secure by Letters Patent, is-

l. The combination of the two propellers,

mounted upon a vertical frame or support and, adapted to be swung completely'around horizontally, with shafts or their equivalents connected independently with each of said propellers and connecting with 'the motive power of the vessel, for the purposes of operating said propellers in opposite directions, substantially as described. 2. In a propelling apparatus provided with two propellers mounted uponA a frame revolving at the stern of a vessel,independentshafts or their equivalents connecting the propellers and the driving apparatus, to drive each propeller independently of the other and in an opposite direction, substantially as set forth.

3. The combination of the. two propellers, mounted upon avertical frame or support and adapted to be swung completely around horizontally, with shafts or their equivalents connected independently with each of said propellers and passing into the vessel, for the purpose of operating said propellers in opposite directions, substantially as described.

4. The combination of two independentlydriven propellers rotating on horizontal axes in opposite directions, mounted opposite to each other upon the same vertical support, with mechanism by which said support may be rotated entirely around its center, substantially as described.

WM. H. MALLORY.

Witnesses:

GEO. H. Evans, WM. A. PoLLooK.

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